title: Antibacterial action of combinations of oxytetracycline, dimethyl sulfoxide, and EDTA-tromethamine on Proteus, Salmonella, and Aeromonas.
abstract: Antibacterial effects against Proteus mirabilis, Salmonella typhimurium, and Aeromonas hydrophila were obtained with subminimal inhibitory concentrations of oxytetracycline and EDTA-tromethamine. Antibacterial effects were not observed with subminimal inhibitory concentrations of dimethyl sulfoxide plus oxytetracycline or with dimethyl sulfoxide plus EDTA-tromethamine. Using a 2-dimensional Microtiter checkerboard technique, inhibitory activities of the various combinations of solutions were studied, and isobolograms were plotted. A synergistic effect was seen with combinations of oxytetracycline and EDTA-tromethamine. The greatest synergistic effect was observed when the mixture was caused to react with P mirabilis. These findings were confirmed by kinetic studies of microbial death, using one-fourth minimal inhibitory concentrations of these preparations.
mesh_terms: D000333:Aeromonas / Q000187:drug effects*; D004121:Dimethyl Sulfoxide / Q000494:pharmacology*; D004347:Drug Interactions; D004492:Edetic Acid / Q000494:pharmacology*; D010118:Oxytetracycline / Q000494:pharmacology*; D011513:Proteus mirabilis / Q000187:drug effects*; D012486:Salmonella typhimurium / Q000187:drug effects*; D013045:Species Specificity; D014325:Tromethamine / Q000494:pharmacology*
chemical_list: D014325:Tromethamine; D004492:Edetic Acid; D010118:Oxytetracycline; D004121:Dimethyl Sulfoxide